Aldosterone 21-esters and 1-dehydro analogues

ABSTRACT

ALDOSTERONE 21-P SUBSTITUTED BENZOATES AND THEIR 1-DEHYDRO-ANALOGUES HAVING PROLONGED ADRENOCORTICAL, HYPERTENSIVE AND GAMMA RAYS PROTECTING ACTIVITY ARE OBTAINED BY PARTIAL ACID HYDROLYSIS OF THE CORRESPONDING NEW 18,21-DI-P SUBSTITUTED BENZOATES.

United States Patent "Te 3,649,620

Patented Mar. 14, 1972 a 649 620 products with a certain frequency. More prolonged activity J has been instead ascribed to aldosterone 21-tr'meth lace- ALDOSTERONE zrfisrhas AND l-DEHYDRO me 1 y ANALOGUES Alberto Ercoli, Milan, Rinaldo Gardi, Cal-ate Brianza, 5 i 278. found 5. 11 a Romano Vitali, Casatenovo, and Giovanni Falcon], F a ex 1 1 an ex E y 1g an Protrac e Camte Brianza, Italy, assignors to Wamer LambeI.t activity and proved to be suitable both for the oral and Company Morris l i NJ. parenteral administration.

N0 Drawing. lfiled Feb. 16, 1970, Ser. No. 11,911 In particular it has been shown that a single adminis- Clanns priority, application Italy, Feb. 19, 1969, tration of the compounds of the present invention can 13,033/69; 10, 1969 25,983/69 0 maintain adrenalectomized rats alive for many months U S C] C07c 173/00 14 Cl and allow an apparently normal development of the alms treated animals which, in spite of the severe operation,

- show a weight increase alike that of intact animals. Aldo- ABSTRACT OF THE DISCLOSURE sterone 21-p-chlorobenzoate in particular, when adminis- 15 tered subcutaneously in a single dose of 0.25 mg. to immature adrenalectomized rats, can maintain them alive for more than 130 days and allow their physical development almost normally.

It is also particularly interesting that the compounds of the invention exhibit their high activity even when orally administered. l-dehydroaldosterone 2l-p-chlorobenzoate, when orally administered in a daily dose of 0.1 nmole to adrenalectomized female rats, is able to maintain the animals alive for several months.

Further the compounds of the present invention give a certain protection against the effects of gamma rays irradiation. Unlike the products heretofore proposed for this purpose, for example cisteamine and AET (S-B-aminoethyl isothiuronium bromide hydrobromide), which are useful only when administered before irradiation (Annals R of the New York Academy of Sciences, 141, 47; 1967),

9 I Q certain new ZI-ester-s of aldosterone, and tehir l-dehydro 0 Ho co analogues, proved to be active in mice also when administered after irradiation.

I Finally, the novel compounds of the present invention 1 exhibit a good hypertensive activity since they are able 0' to induce a very remarkable increase in the blood pressure of adrenalectomized rats.

Aldosterone 2l-p substituted benzoates and their l-dehydrcyanalogues having prolonged adrenocortical, hypertensive and gamma rays protecting activity are obtained by partial acid hydrolysis of the corresponding new 18,21-di-p substituted benzoates. 20

The present invention refers to novel long-acting 21- esters of a steroid selected from the group consisting of aldosterone and l-dehydroaldosterone, to a process for 25 their prepa'ration'and'to pharmaceutical compositions containing said 2l-esters as active ingredients.

The novel compounds of the invention are characterized by the following formula:

wherein -R represents lower alkyl, halogen, lower alkoxy,

cycloalkyloxy or nitro and Z represents a carbon-carbon 40 PHARMACOLOGICAL DATA single bond or a carbon-carbon double bond.

The term lower alkyl, as used herein, comprises hy- (A) Survival of adrenalectomized animals drocarbon radicals containing from one to four carbon atoms, inclusive, i.e. methyl, ethyl, propyl, butyl and their T p m n were p f rm n im r nisomers. The lower alkoxy group is an ether group conaleetomiled p g y Tats each Weighing about taining 21 lower alkyl as defined above and the c'yclo- Nine tWelVe animals P group were employedalkyloxy group includes a cycloaliphatic hydrocarbon Th C mpounds under examination were parenterally or radical containing from three to seven carbon atoms, in- Orally administered Within the Second y after adrenclusive. alectomy. During the experiments the animals were fed It will be appreciated that the new 2l-esters of this 50 Grollman diet (End gy, 9, 855; 1941). invention can exist in three tautomeric forms in accord- The experiments Were divided into two groups accordance with the three tautomeric forms assigned to aldog t0 the kind of administration carried sterone and l-dehydroaldosterone (aldehyde, hemiacetal In the first group consisting of five different p and bis-epoxide forms) which are represented by the ments the results of which are summarized in Table I- following scheme: the compounds were parenterally administered and the CH OH Ht!) CH Ol-t O CHZOH HO OHC CO where Z is as defined above. activity of some aldosterone-Zl-esters of the invention It is known (F. Gross; Symposium CIBA, 9, 173; 1961) was compared to that of aldosterone itself and to that that aldoesterone and its Zl-acetate possess pronounced of other already known aldosterone 21-esters. adrenocortical activity which, however, dies out in a very In experiment No. 1, performed on rats which besides short time. Therefore, in order to obtain a valuable therabeing adrenalectomized were also hypophysectomized peutic effect it is necessary to administered said active aldosterone 2l-anisate and aldosterone 2l-p-nitrobenzo- 3 ate, are compared with the free aldosterone given at a times greater dose.

In experiment No. 3 the activity of aldosterone 21-pchlorobenzoate is compared with that of aldosterone 21- trimethylacetate which, as well known, is the only one derivative to which a certain protracted activity has been ascribed (Symposium CIBA, 9, 173; 1961).

In experiment No. 4 the activity of aldosterone 21-pchlorobenzoate is compared with that of aldosterone 21- benzoate, described in US. Pat. 2,862,925.

In experiment N0. 2 the activity of aldosterone 21-ptoluate is given in comparison to the controls and in experiment No. 5 is reported the activity of aldosterone 2l-p-chlorobe'nzoate, at two difierent dosage levels.

4 TABLE 11 Survival on the Compounds tested: th day, percent (Controls irradiated and not treated) 20 Aldosterone 21-p-chlorobenzoate 34 l-dehydroaldosterone 21-p-ch10robenzoate 27 TABLE I Num- Day mole ber of Route of Experiment (single Survival of Vehitreatadministra- Number Compounds tested (dose) (days) rats Sex ele 1 ment 2 ti on 1 (2278) (Controls) 3. Gil). 4 9 F 1 Intramuscular.

Aldosterone 5 6. :0. 2 9 F 1 Do. Aldosterone 21-anisate 1 47.71171 10 F 1 Do. Aldosterone 21-p-m'trobenzoate 1 48. 93:10. 5 10 F 1 Do.

2 (2412 (Controls) 5.4=l=0.14 10 M 1 Subcutaneous.

Aldosterone 21-p-toluate l 57. 0:1;6.7 10 M 1 Do.

3 (2591) Aldosterone 2l-trimethylacetate 0. 5 8. 511:0. 28 11 F 1 Do. Aldosterone 21-p-ch1orobenzoate 0. 5 64. 4i5. 66 9 F 1 Do.

4 (2459) (Controls) 12 M 2 Do. Aldosterone 21-benzoate 11 M 2 Do. Aldosterone 21-p-ehlorobenzoate 12 M 2 Do.

5 (2277) do 0.25 81. 55:19. 0 10 M 1 Intramuscular.

. .d0 0.5 130. 6123. 7 12 M 1 D0.

1 SV=suspending vehicle No. 17,874 (R1. Dorfmen, "Methods in Hormone Research Academic Press, 2, 709; 1962). Oil= castor oil-sesame 011 1:1.

2 Adrenalect-omy on day 1.

It clearly results from Table I that, while free aldosterone is practically devoid of any protracted activity and aldosterone ZI-trimethylacetate and 21-benzoate only display it in a rather scarce degree, the compounds of the present invention possess an exceptionally prolonged activity since they are able to maintain adrenalectomized rats alive for at least two months and in some cases even for 3-5 months.

Further, from experiments 3 and 4 it is shown that aldosterone 2l-p-chlorobenzoate exhibits an activity extremely more prolonged than that of both aldosterone 21-benzoate and aldosterone Zl-trimethylacetate.

In the second group of experiments we tested the activity of aldosterone 21-p-chlorobenzoate and l-dehydroaldosterone-2l-p-chlorobenzoate when orally administered. The compounds were proved at three dose levelsnamely 0.01, 0.1 and 1 ,umoles daily. On day 115, 6 animals treated with aldosterone-2l-p-chlorobenzoate (1 ,umole) and 5 animals treated with l-dehydroaldosterone- 2.1-p-chlorobenzoate (0.1 nmole) were still alive.

From the above it is evident the extreme interest of the compounds of the invention as long-lasting adrenocortical agents also when administered by oral route.

(B) Protection against the elfect of gamma rays radiations The experiments were performed on groups of 30 adult female mice which had been irradiated by 877 rads in 10 minutes.

On the day following irradiation aldosterone 21-pchlorobenzoate, and l-dehydroaldosterone-Zl-p-chlorobenzoate, were administered by subcutaneous route in a single dose of 0.3 mole in 0.2 cc. of SV (suspending vehicle No. 17,874, see Table I). 30 days after irradiation the survival was determined as a percentage of the number of animals still alive over the treated animals.

(C) Efiect on blood pressure TABLE III Percent increase pressure after- Experiment Number Compound tested 6 days 12 days (2668) Aldosterone 2l-p-chlorobenz-oats 36 1-dehydro-aldosterone21-p-ehloro- 100 benzoate.

A further experiment (2684) was carried out on intact male Wistar rats and aldosterone-2l-p-chlorobenzoate and l-dehydro-aldosterone-Zl-p-chlorobenzoate were intravenously administered at the dose of 0.1 g/ 0.1 ml. of S.V. Determination of the arterial blood pressure effected 3, 9 and 27 minutes after the treatment pointed out for both compounds a sudden and remarkable increase of the blood pressure.

.From the above it is evident the hypertensive elfect showed by the compounds of the invention either when administered in low or high dose.

The new 21-e'sters of the present invention, therefore, can be considered useful as protective agents against gamma rays radiation of Whatever origin and for the treatment of states of hypotension, or of chronic or also acute (both of infective and traumatic origin) adrenocortical insufiiciency.

Thanks to their exceptional properties the novel compounds of the present invention can be administered in a single relatively low dose to obtain a protracted effect.

In accordance with the present invention the compounds of Formula I are formulated in pharmaceutical compositions in admixture with inert pharmaceutical solid or liquid carriers suitable for the oral or parenteral administration.

For example the compounds of the invention may be dissolved or suspended either in water or in an oil such as sesame oil, peanut oil, corn oil, coconut oil, cottonseed oil, linseed oil, olive oil, monoand diglycerides as well as synthetic triglycerides, that is esters of glycerol with high molecular weight aliphatic acids either saturated or unsaturated, to obtain ampuls or multiple dose fiacons.

Further they can be presented as suppositories in admixture with 'suppository bases such as, for example, cocoa butter, beeswax, higher aliphatic alcohols, glycols, cholesterol, zinc stearate and like or can be mixed with usual suitable carriers and presented as tablets, troches, pills, sugar-coated pills, capsules for the oral adminis tration.

The compositions for the present invention contain the active ingredient in an amount of from about 0.01 to about 20 mg, preferably from 0.025 to 10 mg. and may be administered in a single dose by intramuscular, subcutaneous intravenous, rectal or oral route.

The novel 2l-esters of the present invention are prepared by partial acid hydrolysis of the corresponding new 18,21-diesters derived from .the semi-acetal form (b) characterized by the following general formula:

o--nc co a II in which R and Z have the above stated meaning.

According to said process, which represents another object of the invention, the new 18,21-diesters intermediates of Formula H are hydrolyzed in the presence of an acid catalyst.

It is advisable that the pH of the medium is maintained below 3 in order that the partial hydrolysis leads to 21-mon0esters selectively. Under these conditions the esterifying group at 21-position is quite stable and consequently the compounds of Formula I are obtained in very high yields.

As an acid catalyst any mineral or organic acid preferably having a pKa lower than 5 can be employed, such as hydrochloric acid, hydrobromic acid, sulphuric acid, p-toluenesulphonic acid, perchloric acid, periodic acid, trichloroacetic acid, oxalic acid, dichloroacetic acid, sulphurous acid, phosphoric acid, fiuoroacetic acid, bromoacetic acid, chloroacetic acid, citric acid, p-nitrobenzoic acid, formic acid or acetic acid. Preferred catalysts are the strong inorganic acids, in particular hydrochloric and perchloric acid and, among organic acids, p-toluenesulphonic acid, haloacetic acids and formic acid.

The reaction can be carried out in the presence of water and/or of a polar solvent at room temperature or by heating the mixture up to a temperature not higher than 80 C. Solvents which can be used include acetone, esters such as, for example, ethyl acetate, or ethers such as, for example, diethyl ether, dioxane or tetrahydrofu rane. When weak acids, e.g. acetic acid, are used as acid catalysts, the same acids can also be employed as solvents.

The end products obtained are isolated according to usual methods, for example by simple filtration or by neutralization of the catalyst, evaporation of the solvent and recrystallization of the residue.

The new aldosterone 18,21-diesters and corresponding l-dehydro-cornpounds intermediates of Formula II which represent a further object of the present invention are generally prepared by complete esterification of aldosterone and l-dehydroaldosterone i.e. by treating these compounds with an excess of an esterifying agent derived from a R-p-substituted benzoic acid, for example an anhydride or a chloride, in the presence of a pyridine base, for example pyridine itself.

In order further to illustrate the invention the following examples are given.

EXAMPLE I To a mixture of 100 cc. of anhydrous chloroform and 20 cc. of pyridine cooled at -20 C. there is added dropwise 20 cc. of p-chlorobenzoyl chloride and then a solution of 10 g. of aldosterone in 50 cc. of pyridine. The mixture is maintained at 20 C. for about 60 minutes and then overnight at 0-5 C. and finally poured into ice water and extracted with methylene chloride. The extract is washed with dilute hydrochloric acid, with a sodium bicarbonate solution and with water, then it is dried on anhydrous sodium sulphate. After elimination of the solvent under vacuum and crystallization of the residue from an ether-methylene chloride mixture, aldosterone 18,21-d-p-chlorobenzoate is obtained;

M.P. 2152l8 C. [a] =+14O (dioxane, c.=0.5%)

Following the same procedure, the following 18,21- diesters are obtained.

Aldosterone 18,2l-di-p-fluorobenzoate Aldosterone 18,2l-di-p-toluate Aldosterone 18,2-1-di-p-nitrobenzoate Aldosterone 18,21-di-anisate Aldosterone 18,21-di-p-ethoxybenzoate EXAMPLE 2 To a suspension of 16 g. of aldosterone 18,21-di-pchlorobenzoate in 1600 cc. of 5% aqueous acetone there is added 32 cc .of 0.5 N perchloric acid and the mixture is heated on a boiling water bath. In about 5 minutes the diester is completely dissolved and within other 15-20 minutes a crystalline product begins to separate. Heating is continued for minutes, then the mixture is left to cool at room temperature. The crystalline product, filtered and washed with ether, gives 6.2 g. of practically pure aldosterone 2l-p-chlorobenzoate. Other 1.5 g. of product of satisfactory purity is obtained by concentration of the mother liquors under vacuum, filtration of the precipitate and digestion with hot acetone.

Recrystallization of the whole product from a methylene chloride-acetone-butanol mixture gives 6.7 g. of pure aldosterone 2l-p-chlorobenzoate, M.P. 231234 C. [a] =+90.5 (dioxane, c.=0.5%)

A 239-240 Ill .4, E} =690 In an analogous manner:

aldosterone 2l-p-fluorobenzoate; M.P. 231232 C.;

aldosterone 2l-p-toluate; M.P. 233235 C.; [a]

+93 (dioxane, c.=0.5%

aldosterone 2l-p-nitrobenzoate, M.P. 211-213 [ah-P 895 (dioxane, c.=0.5%

A... 243-244 y, l m.=487

aldosterone 21-anisate, M.P. 223-224 C.; ]13

(dioxane, c.=0.5%

aldosterone 2l-p-ethoxybenzoate, M.P. 164-166" aldosterone 21-p-cyclopentyloxybenzoate, M.P. 163164 C.; [a] =|-7O (dioxane, c.=0.5%);

Am. 250-251 mp, E;%,, =45e are obtained.

EXAMPLE 3 To a mixture of 100 cc. of anhydrous chloroform and 20 cc. of pyridine cooled to 20 C. there is added dropwise 20 cc. of p-chlorobenzoyl chloride and then a solution of 10 g. of l-dehydro-aldosterone in 50 cc. of pyridine. The mixture is maintained at 20 C. tor about 60 minutes, then overnight at 5 C. and finally poured into ice-water and extracted with methylene chloride. The extract is washed with dilute hydrochloric acid, with a sodium bicarbonate solution and with water, then it is dried over anhydrous sodium sulphate. After elimination of the solvent under vacuum and crystallization of the residue from an ether-methylene chloride mixture, l-dehydroaldosterone 18,2l-di-p-chlorobenzoate is obtained.

Operating in the same manner, the following 18,21- diesters are obtained:

l-dehydro-aldosterone 18,21-di-p-fluorobenzoate, l-dehydro-aldosterone 18,21-di-p-nitrobenzoate, l-dehydro-aldosterone 18,21-di-p-toluate, l-dehydro-aldosterone 18,21-di-anisate, l-dehydro-aldosterone 18,21-di-p-ethoxybmzoate.

EXAMPLE 4 To a suspension of 16 g. of l-dehydro-aldosterone 18,2l-di-p-chlorobenzoate in 1600 cc. of 5% aqueous acetone there is added 32 cc. of 0.5 N perchloric acid and the mixture is heated on a boiling water bath. In about 5 minutes the diester is completely dissolved and within -20 minutes a crystalline product begins to separate. Heating is maintained for about 90 minutes, then the mixture is allowed to cool at room temperature. The crystalline product, filtered and Washed with ether, gives l-dehydroaldosterone 21-p-ch1orobenzoate practically pure. Recrystallization of the product from a methylene chloride-acetone-butanol mixture gives pure l-dehydro-aldosterone 21-p-chlorobenzoate, melting at 227229 C.; [a] .=+43+ -2 (dioxane, c.-=0.5%)

max. 40-241 m 44 In an analogous manner are obtained: l-dehydro-aldosterone 21-p-nitrobenzoate, melting at 218220 C.; [a] =]-47.5 (dioxane, c.=0.5%)

a... 250-252 mi, EittFiar EXAMPLE 5 50 mg. of aldosterone 21-p-chlorobenzoate are dissolved in 200 cc. of a 1:1 mixture of sesame oil-castor oil and the solution is poured into 2 cc. ampuls to obtain ampuls each containing 0.5 mg. of active substance.

EXAMPLE 6 Operation is carried out as in Example 5 using instead of aldosterone 21 p chlorobenzoate, l-dehydro-aldosterone 21-p-chlorobenzoate.

EXAMPLE 7 100 mg. of aldosterone 2l-anisate are dissolved in 200 cc. of sesame oil and the solution is poured into 2 cc.

ampuls to obtain ampuls each containing 1 mg. of active substance.

EXAMPLE 8 A suspension having the following composition is prepared:

Aldosterone 21-p-chlorobenzoate5 g. Carbowax 400029 g.

Tween -4 cc.

Bidistilled water to 1000 cc.

The suspension so obtained is poured into 1 cc. ampuls to obtain ampuls each containing 5 mg. of active product.

EXAMPLE 9 A suspension having the following composition is prepared:

Aldosterone 21-p-chlorobenzoate-50 g.

Carbowax 4000290 g.

Tween 80-40 cc.

Novadral [d,l-1-(3' hydroxypheny1)-2-amino ethanol hydrochloride, Diwag Chemische Fabriken G.rn.b.H., Berlin]l00 g.

Bidistilled water to 10,000 cc.

The suspension so obtained is poured into Ice ampuls to obtain ampuls each containing 5 mg. of active'pr'oduct.

We claim:

1. A compound of the formula:

References Cited UNITED STATES PATENTS 12/ 1958 Reichstein et a1. '260-239.55 5/1959 Hogg et al 260397.4S 5/ 1961 Kerwin et a1: ;260'239;55 3/1968 Gardner et a1; "260 2 39.55

HENRY A. FRENCH, Primary Examiner US. Cl. X.R. 

